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Theory of optical conductivity in detwinned YBa$_2$Cu$_3$O$_{y}$

T. Zhou·Jian-Xin Li·Z. D. Wang
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Abstract

We study theoretically the chain and in-plane optical conductivities of detwinned YBa$_2$Cu$_3$O$_{y}$. We elaborate that the chain is superconducting for $y>6.67$ while insulating for $y<6.67$ due to the competition between the plane-chain coupling and the antiferromagnetic order, corresponding to a superconductor-insulator transition. Stemming also from the coupling between the plane and chain, a new peak emerges at a low frequency in the in-plane spectra in the superconducting state, while it disappears in the normal state. Our scenario accounts satisfactorily for very recent experiments.

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T. Zhou, Jian-Xin Li, Z. D. Wang. 2006-08-09. Theory of optical conductivity in detwinned YBa$_2$Cu$_3$O$_{y}$. https://arxiv.org/abs/cond-mat/0608207

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